Discrimination of heavy metal acclimated environmental strains by chemometric analysis of FTIR spectra

Kepenek E. S., Severcan M., GÖZEN A. G., SEVERCAN F.

ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, cilt.202, 2020 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 202
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1016/j.ecoenv.2020.110953
  • Dergi Adı: ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Artic & Antarctic Regions, BIOSIS, CAB Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, EMBASE, Environment Index, Food Science & Technology Abstracts, Geobase, Greenfile, MEDLINE, Metadex, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Anahtar Kelimeler: Bacteria, ATR-FTIR, PCA, HCA, SIMCA, Pb, Cd, TRANSFORM-INFRARED-SPECTROSCOPY, GRAM-NEGATIVE BACTERIA, IR SPECTROSCOPY, RESISTANCE MECHANISMS, MICROBIAL COMMUNITIES, MULTIVARIATE-ANALYSIS, LEAD RESISTANCE, IDENTIFICATION, CLASSIFICATION, CADMIUM
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Heavy metal acclimated bacteria are profoundly the preferred choice for bioremediation studies. Bacteria get acclimated to toxic concentrations of heavy metals by induction of specific enzymes and genetic selection favoring new metabolic abilities leading to activation of one or several of resistance mechanisms creating bacterial populations with differences in resistance profile and/or level. Therefore, to use in bioremediation processes, it is important to discriminate acclimated bacterial populations and choose a more resistant strain. In this study, we discriminated heavy metal acclimated bacteria by using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy and multivariate analysis methods namely Hierarchical Cluster Analysis (HCA), Principal Component Analysis (PCA) and Soft Independent Modeling of Class Analogy (SIMCA). Two acclimation methods, acute and gradual, were used which cause differences in molecular changes resulting in bacterial populations with different molecular and resistance profiles. Brevundimonas sp., Gordonia sp., and Microbacterium oxydans were exposed to the toxic concentrations of Cd (30 mu g/ml) or Pb (90 mu g/ml) by using broth medium as a growth media. Our results revealed that PCA and HCA clearly discriminated the acute-acclimated, gradual acclimated, and control bacteria from each other in protein, carbohydrate, and whole spectral regions. Furthermore, we classified acclimated (acute and gradual) and control bacteria more accurately by using SIMCA with 99.9% confidence. This study demonstrated that heavy metal acclimated and control group bacteria can be discriminated by using chemometric analysis of FTIR spectra in a powerful, cost-effective, and handy way. In addition to the determination of the most appropriate acclimation procedure, this approach can be used in the detection of the most resistant bacterial strains to be used in bioremediation studies.